This is how I've gotten to MR26 on console and I expect to continue :p
The post description sounds like it means "Warframe", but I'd be really interested to see what the story would be like without Ballas, the single big bad orokin who personally caused so many of the events of the plot. I'm more interested in the aftermath of the orokin system than the villainy of one man.
unless im misunderstanding the problem, I don't think OP could get the fortuna kitguns given their current predicament.
Though, a sporelacer secondary would rip
My understanding is that certain frame abilities, such as Roar, Eclipse and Xata's Whisper are tagged as "damage boosting" abilities, and can only be subsumed onto other damage boosting abilities, specifically to prevent that interaction.
source info can be found at this section of the wiki: https://warframe.fandom.com/wiki/Helminth#Injecting_and_Replacing_Abilities
As others might have explained, the "event" which lasts a couple weeks will grant access to the Kullervo prison island regardless of the current spiral. After the event is over, and on normal runs, the hold will only show up on certain spirals and not others, similar to Archarbor